WTPN31 PGTW 251400 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE WARNING// RMKS/ 1. TROPICAL STORM 16W (GONI) WARNING NR 047 DOWNGRADED FROM TYPHOON 16W 01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 251200Z --- NEAR 36.4N 131.6E MOVEMENT PAST SIX HOURS - 025 DEGREES AT 12 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY BECOMING EXTRATROPICAL RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 115 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 36.4N 131.6E --- FORECASTS: 12 HRS, VALID AT: 260000Z --- 39.0N 132.3E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL VECTOR TO 24 HR POSIT: 355 DEG/ 14 KTS --- 24 HRS, VALID AT: 261200Z --- 41.8N 132.1E MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT WIND RADII VALID OVER OPEN WATER ONLY EXTRATROPICAL --- REMARKS: 251500Z POSITION NEAR 37.0N 131.8E. TROPICAL STORM (TS) 16W (GONI), LOCATED APPROXIMATELY 128 NM NORTH OF IWAKUNI, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A FULLY EXPOSED AND ELONGATED LOW LEVEL CIRCULATION CENTER WITH DEVELOPING FRONTAL CHARACTERISTICS. THIS IS ESPECIALLY EVIDENT ALONG THE NORTHERN PERIPHERY WHERE THE SYSTEM IS ENVELOPED IN THE MID-LATITUDE WESTERLY FLOW. A RECENT AMSU CROSS-SECTION ANALYSIS FURTHER SHOWS THAT TS GONI HAS BEGUN EXTRA-TROPICAL TRANSITION WITH A WEAKER WARM-CORE THAT HAS DROPPED TO 4-KM AND A COLD-CORE DEVELOPING NEAR 14-KM. THE FSU CYCLONE PHASE EVOLUTION GRAPHIC REVEALS THAT TS 16W IS IN THE PROCESS OF TRANSITIONING FROM A WARM-CORE TO A COLD-CORE SYSTEM. THE INITIAL POSITION IS BASED ON THE EIR LOOP AND A 250838Z WINDSAT MICROWAVE IMAGE WITH GOOD CONFIDENCE. TS GONI WILL CONTINUE TO WEAKEN AS IT TRACKS POLEWARD INTO SEA SURFACE TEMPERATURES BELOW 26 CELSIUS AND WILL CONTINUE EXTRA-TROPICAL TRANSITION (ETT) AS IT EMBEDS DEEPER INTO THE BAROCLINIC ZONE. TS 16W IS FORECAST TO COMPLETE ETT IN 12 HOURS. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT LENDING TO HIGH CONFIDENCE IN THE JTWC FORECAST. THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 251200Z IS 18 FEET./=